Apparatus for tapering flexible tubes

ABSTRACT

Apparatus for tapering cylindrical tubes formed of a flexible material comprising a supporting member having a generally cylindrical cross section adapted to be inserted into a cylindrical flexible tube to thereby support the tube and having passage means defined in the support member to transmit a fluid pressure to the periphery of the support member, a matrix having a substantially conical cross section into which the support member, upon which is mounted a tube, is inserted and a moveable sleeve member adapted to be engaged in a sealing relationship with the base of the flexible tube which is moveable in response to fluid pressure to continuously maintain the sleeve member in a sealing engagement with the base of the tube while a fluid pressure is supplied to the passage means in the support member to expand the wall of the flexible tube so that it corresponds to the configuration of the matrix.

United States Patent 1 v 3 5, 01

Couland Feb. 13, 1973 [54] APPARATUS FOR TAPERING 3,358,489 12/ 1967 Hutchins ..72/56 FLEXIBLE TUBES Primary Examiner-Richard J. Herbst [76] Inventor: Roger Couland, 51, rue Maurice Philippot, 92 Fontenay-aux-Roses, Atmmey McDougan Hersh & Scott France 70 57 ABSTRACT l [22] Filed March 9 Apparatus for tapering cylindrical tubes formed of a PP 15,735 flexible material comprising a supporting member having a generally cylindrical cross section adapted to be [30] Foreign Application Priority Data inserted into a cylindrical flexible tube to thereby support the tube and having passage means defined 1n the March 18, 1969 France ..6907626 Support member to transmit a fluid pressure to the periphery of the support member, a matrix having a [52] US. Ll ..72/58, 72/62 Substantially conical cross Section into which the Sui} [51] 111i. Cl. ..B2ld 26/04 port member upon which i mounted a tube, iS i [58] Field of Search ..72/57, 58, 60, 61, 62, 370; Sened and a moveable Sleeve member adapted to be 29/421 engaged in a sealing relationship with the base of the flexible tube which is moveable in response tofluid [56] References C'ted pressure to continuously maintain the sleeve member UNITED STATES pATEN-is in a sealing engagement with the base of the tube while a fluid pressure is supplied to the passage means 3,160,130 12/1964 Pes ak ..29/421 in the support member to expand the wall of the fieXi 3,043,254 7/ i962 l-leidmann ..29/421 l tube so that it col-responds to the configuration of 2,821,945 2/1958 Peccerill ..72/62 the matrix 3,151,590 10/1964 Garvin ..72/61 2,038,304 4/1936 Middler ..72/56 11 Claims, 1 Drawing Figure APPARATUS FOR TAPERING FLEXIBLE TUBES This invention relates to apparatus for tapering cylindrical tubes formed of a flexible material.

Flexible metal tubes are well known for use in packaging as containers for toothpaste, foodstuffs and a wide variety of other materials. Such tubes are generally delivered for filling in the form of a cylindrical container which is open at the end opposite of the removable cap. However, tubes of the type described present transportation and storage problems in that, because of their flexible nature, they are easily deformed or crushed. One solution to these transportation and storage problems is to form the tubes so that the sidewalls have a cross section which is generally conical whereby the individual tubes can be stacked one inside another. It has been found that such stacks of flexible tubes have considerably reduced bulk and are considerably less susceptible to deformation or crushing as compared to individual tubes forming the stack since the walls of the stacked tubes are substan tially in surface contact each with the other whereby the sidewalls of adjacent tubes in the stack tend to reinforce each other.

Various methods for tapering flexible tubes to provide tubes having conical cross sections have been proposed, including widening the base of the flexible tube by shaping on a mandrel or by dilation. However, these methods are unacceptable for the production of conical tubes on a commercial scale.

It has also been proposed to provide conical tubes by means of a punch covered with a envelope of rubber whereby the punch is inserted into the cylindrical tube, which is then dilated by placing the envelope inside a mandrel having an internal surface of the desired conical shape and blowing air into the envelope. However, the rubber envelopes have not been practical since they are easily broken and must be frequently replaced.

It is accordingly an object of the present invention to provide apparatus which produces conical flexible tubes which overcomes the aforementioned disadvantages.

It is a more specific object of the present invention to provide apparatus for producing flexible conical tubes from cylindrical conical tubes by pneumatic dilation wherein a cylindrical tube is placed inside of a conical matrix and a fluid is forced into the tube to expand the wall of the tube to correspond to the interior surface of the material.

These and other objects and advantages of the invention will appear hereinafter and, for purposes of illustration, but not of limitation, an embodiment of the invention is shown in the accompanying drawing wherein:

' The FIGURE is a schematic view in cross section of an apparatus embodying the features of the present invention.

The concepts of the present invention reside in apparatus for tapering cylindrical tubes formed of a flexible material in which the cylindrical tube is placed inside of a matrix, the interior of which has a generally conical cross section, and thereafter, a fluid is forced into the tube whereby the fluid exerts a pressure on the wall of the flexible tube causing the wall to expand outwardly so that the tube acquires the generally conical cross section of the matrix.

The effect of the fluid pressure is to expand the side wall of the flexible tube whereby the length of the wall is decreased or shortened, and the diameter or width of the base or open end of the tube is increased. Accordingly, one of the features of the present invention resides in a moveable sleeve member having at least one inclined wall which is continuously engaged with the open end of the tube to continuously provide a tight seal at the base of the tube in order to provent leakage of the fluid pressure contained within the tube as the width of the open end is increased and the height decreased.

Referring now to the drawing, there is shown a schematic view of the device of the present invention. The portion of the drawing to the left of line A-B represents the apparatus prior to actuation, and the portion to the right of line A-B illustrates the apparatus after a flexible tube has been tapered.

Referring initially to the drawing on the left side of line A-B, there is shown a flexible tube defined by flexible sidewall 1 having a generally cylindrical cross sec tion, and having a cap 1" releasably engaged with one end of the tube. As shown in this figure, the cap 1'' is threadably engaged with the top of the tube, although it will be understood by those skilled in the art that other types of removable caps may be employed in lieu of that specifically described in this figure.

Flexible tube 1 is mounted on a support member 2 having a substantially cylindrical cross section which: is adapted to substantially fill the interior of tube 1. Support member 2 is provided with a system of opening therethrough which communicate with the end and periphery of the support member which are adapted to transmit a fluid through the support member. As shown, the openings include a central opening 3' extending through nipple 4 by means of a tube 5. The tube I mounted on support member 2 is adapted to be positioned in a first housing member in the form of a conical matrix 11 having a plurality of openings 12 through the walls thereof which communicate with the space 13 defined by the interior wall of the matrix 11 and the exterior wall of tube 1.

One end of the matrix housing is removably engaged, such as by threadable engagement, with a second housing member 6 defining a central cavity 14. Positioned within central cavity 14 is an annular sleeve member 7 which is moveable within central cavity 14 relative to housing member 6. In order to provide a tight seal between moveable sleeve member 7 and the side walls of central cavity 14, there is provided sealing means 8 on sleeve member 7. As shown in the figure, sleeve member 7 is displaced relative to housing member 6 in response to a fluid pressure from a fluid fed to central cavity by means of an opening 9 communicating therewith.

The lower end of annular sleeve member 7 circumscribes tube 5 which connects the central opening 3' of support member 2 whereby the tube extends through the axial opening of the annular sleeve member 7 and the sleeve member is moveable between tube 5 and housing 6. The end 10 of sleeve member 7 facing support member 2 is tapered so as to have the configuration of an annular truncated cone, the central opening of which is adapted to receive a cylindrical project 15 on the end of support member 2 opposite the cap 1" of tube '1. The cylindrical projection 15 on support member 2 has an axial length sufficient to permit the truncated cone end 10 of sleeve member 7 to be displaced toward the tube and a diameter sufficiently less than that of the support member 2 that the inclined wall of truncated cone end 10 of sleeve member 7 is adapted to continuously engage the base of tube 1 in a sealing engagement therewith as the base of the tube is expanded and the height decreased.

In use, a flexible tube, such as a flexible tube formed of metal or the like, is mounted on support member 2, and the housing elements 6 and 11 are assembled. Thereafter, a fluid, such as air under pressure, is fed to nipple 4 and to opening 9. The fluid fed to nipple 4 is transmitted through tube into the system of openings 3 and 3' in support member 2 and is further transmitted to the periphery of support member 2 whereby fluid pressure is exerted on the interior of tube sidewall 1 thereby pushing the wall 1 outwardly toward the interior wall of matrix 11. Air which may be trapped in space 13 between matrix 1 1 and tube 1 is permitted to escape through openings 12 as the wall 1 is expanded.

At the same time, the fluid pressure introduced to central cavity 14 by opening 9 causes sleeve member 7 to be displaced toward tube 1 whereby the inclined wall of sleeve member 7 further serves to displace or expand wall 1 of the flexible tube outwardly as well as serves to insure a tight seal at all times between the end of tube 1 and sleeve member 7 to prevent uncontrolled fluid leakage in the system as the length of tube 1 is shortened and the base is increased or widened.

As is shown on the right hand side of line A-B in the drawing, the wall of tube 1 is forced outwardly in response to the fluid pressure exerted by the fluid injected through passages 3 and 3' of the support member 2 until the wall 1 of the tube is substantially in surface contact with the wall of matrix 11 whereby the tube has a conical configuration corresponding to that of the interior surface of matrix 11. As soon as the tube has acquired the desired conical shape, the sources of fluid pressure are shut off, the matrix is removed, and the tube is ejected from the apparatus, as by the use of a fluid pressure, or otherwise passed on to another work station.

. While the apparatus of the present invention has been described with reference to the production of conical tubes formed of flexible metals, it will be appreciated by those skilled in the art that the apparatus of the invention can also be used to provide conical tubes formed of other flexible materials such as plastics or the like.

It will be apparent from the foregoing that l have provided a new and improved apparatus for forming a cylindrical flexible tube into a conical flexible tube which can be stacked for use in transportation and storage whereby stacks of the conical tubes occupy considerably less space and have considerably increased resistance to deformation and crushing during storage, transportation and handling. In addition, the apparatus of the present invention is both simple and efficient so as to provide conical tubes which minimize expense.

It will be understood that various changes may be made in the details of construction and use without departing from the spirit of the invention, especially as defined in the following claims.

I claim:

1. Apparatus for tapering cylindrical tubes formed of a flexible material comprising a substantially rigid support member having a substantially cylindrical cross section adapted to be inserted into a cylindrical flexible tube to substantially fill the flexible tube, said support member having passage means therein adapted to transmit a fluid under pressure to the wall of the flexible tube mounted on said support member, a matrix having a substantially conical cross section, said matrix being adapted to receive said support member with a flexible tube mounted thereon, a housing member, said housing member defining a central cavity therein, and a movable sleeve member having the configuration of an annular truncated cone adapted to be engaged in a sealing relationship with the open base of a flexible tube mounted on said support member in response to a fluid under pressure in said central cavity whereby a fluid under pressure supplied to said passage means causes expansion of the wall of the flexible tube while said sleeve member is continuously displaced by a fluid under pressure to a sealing relationship with the open base of the flexible tube to maintain fluid pressure on the wall of the flexible tube during expansion of the wall of the flexible tube.

2. An apparatus as defined in claim 1 wherein said housing member is releasably engaged with said matrix.

3. An apparatus as defined in claim 1 wherein the interior walls of said matrix define a cone.

4. An apparatus as defined in claim 1 wherein said sleeve member is an annular sleeve member being moveable relative to said housing member in said central cavity.

5. An apparatus as defined in claim 1 which includes sealing means between said sleeve member and the wall of said central cavity.

6. An apparatus as defined in claim 1 wherein said matrix has an opening in the walls thereof communicab ing with the interior of said matrix to permit the escape of air trapped between the wall of said matrix and the wall of a flexible tube mounted on said support member.

7. An apparatus as defined in claim 1 which includes a cylindrical projection on said support member, said projection being adapted to be received in said central opening in said sleeve member and having a diameter less than the diameter of said support member to permit said end of said sleeve member to sealingly engage the base of a flexible tube mounted on said support member.

8. An apparatus as defined in claim 1 which includes tube means extending through saidcentral cavity and communicating with said passage means to supply a fluid under pressure to said passage means.

9. An apparatus as defined in claim 8 wherein said tube means extend through a central opening in said sleeve member whereby said sleeve member is moveable relative to said housing member between the walls of said central cavity and said tube means.

10. An apparatus as defined in claim 1 which includes means to supply a fluid pressure to said central cavity whereby said sleeve member is displaced toward said support member.

11. An apparatus as defined in claim 1 wherein said projection has a length sufficient to permit said sleeve member to penetrate the base of a flexible tube as the height of the tube is decreased and the diameter of 'the base of the tube is increased during the expansion of the flexible tube. 

1. Apparatus for tapering cylindrical tubes formed of a flexible material comprising a substantially rigid support member having a substantially cylindrical cross section adapted to be inserted into a cylindrical flexible tube to substantially fill the flexible tube, said support member having passage means therein adapted to transmit a fluid under pressure to the wall of the flexible tube mounted on said support member, a matrix having a substantially conical cross section, said matrix being adapted to receive said suppOrt member with a flexible tube mounted thereon, a housing member, said housing member defining a central cavity therein, and a movable sleeve member having the configuration of an annular truncated cone adapted to be engaged in a sealing relationship with the open base of a flexible tube mounted on said support member in response to a fluid under pressure in said central cavity whereby a fluid under pressure supplied to said passage means causes expansion of the wall of the flexible tube while said sleeve member is continuously displaced by a fluid under pressure to a sealing relationship with the open base of the flexible tube to maintain fluid pressure on the wall of the flexible tube during expansion of the wall of the flexible tube.
 1. Apparatus for tapering cylindrical tubes formed of a flexible material comprising a substantially rigid support member having a substantially cylindrical cross section adapted to be inserted into a cylindrical flexible tube to substantially fill the flexible tube, said support member having passage means therein adapted to transmit a fluid under pressure to the wall of the flexible tube mounted on said support member, a matrix having a substantially conical cross section, said matrix being adapted to receive said suppOrt member with a flexible tube mounted thereon, a housing member, said housing member defining a central cavity therein, and a movable sleeve member having the configuration of an annular truncated cone adapted to be engaged in a sealing relationship with the open base of a flexible tube mounted on said support member in response to a fluid under pressure in said central cavity whereby a fluid under pressure supplied to said passage means causes expansion of the wall of the flexible tube while said sleeve member is continuously displaced by a fluid under pressure to a sealing relationship with the open base of the flexible tube to maintain fluid pressure on the wall of the flexible tube during expansion of the wall of the flexible tube.
 2. An apparatus as defined in claim 1 wherein said housing member is releasably engaged with said matrix.
 3. An apparatus as defined in claim 1 wherein the interior walls of said matrix define a cone.
 4. An apparatus as defined in claim 1 wherein said sleeve member is an annular sleeve member being moveable relative to said housing member in said central cavity.
 5. An apparatus as defined in claim 1 which includes sealing means between said sleeve member and the wall of said central cavity.
 6. An apparatus as defined in claim 1 wherein said matrix has an opening in the walls thereof communicating with the interior of said matrix to permit the escape of air trapped between the wall of said matrix and the wall of a flexible tube mounted on said support member.
 7. An apparatus as defined in claim 1 which includes a cylindrical projection on said support member, said projection being adapted to be received in said central opening in said sleeve member and having a diameter less than the diameter of said support member to permit said end of said sleeve member to sealingly engage the base of a flexible tube mounted on said support member.
 8. An apparatus as defined in claim 1 which includes tube means extending through said central cavity and communicating with said passage means to supply a fluid under pressure to said passage means.
 9. An apparatus as defined in claim 8 wherein said tube means extend through a central opening in said sleeve member whereby said sleeve member is moveable relative to said housing member between the walls of said central cavity and said tube means.
 10. An apparatus as defined in claim 1 which includes means to supply a fluid pressure to said central cavity whereby said sleeve member is displaced toward said support member. 